Existing data processing systems allow for the tracking of data and/or the recording of the status of users of the data. For example, International Business Machines provides a system, referred to as a Data Base Recovery Control System (DBRC), for maintaining an inventory of the Information Management System (IMS) subsystems that are currently sharing data bases. In particular, when IMS wants to use a data base, it registers this usage with DBRC.
In addition to the above, techniques are available for recording where data is located on direct access storage devices (DASD). As one example, a volume table of contents (VTOC) is provided for indicating location of data. Further, a catalog may be provided, which can be used as a pointer to information stored on DASD.
In another example, a technique for maintaining the status of sessions within a network system is described in U.S. Pat. No. 5,027,269, entitiled "Method and Apparatus for Providing Continuous Availability of Applications in a Computer Network," issued on Jun. 25, 1991 and assigned to International Business Machines. As described in the patent, session states, including states for suspended sessions, are tracked for future recovery actions.
The above techniques are disadvantageous, however, because there is no readily recognizable correlation of data and the users of that data. Data and the status of users usually has to be kept in case recovery is needed. As there is no correlation between data and the users of data, there is no automatic reuse of storage by software management systems. Further human intervention or program extensions are required for cleanup or recovery synchronization. The requirement of synchronization adds complexity to the system, degrades system performance and limits resource reuse.